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Advanced search is divided into two main parts, and one or more groups in each of the main parts. The main parts are the "Search for" (including) and the "Remove from search" (excluding) part. (The excluding part might not be visible until you hit "NOT" for the first time.) You can add new groups to both the including and the excluding part by using the buttons "OR" or "NOT" respectively, and you can add more search options to all groups through the drop down menu on the last row (in each group).

For a result to be included in the search result, is it required to fit all added including parameters (in at least one group) and not fit all parameters in one of the excluding groups. This system with the two main parts and their groups makes it possible to combine two (or more) distinct searches into one search result, while being flexible in removing results from the final list.

Historically, residential property is limited to the area needed for the property to substantially have the character of a residential plot. An increased demand for an attractive rural housing resulted in changes to property law, which made it possible to form large residential properties with combined purposes, all in line with the existing rural policy. Still, however, there were restrictions to bring forest land to residential plots for the protection of the productive forestry. The Swedish mapping, cadastral and land registration authority (Lantmäteriet) have therefore created working recommendations to facilitate the opportunity to incorporate forest plots, including the collection of firewood for household use. This study had the aim to investigate how the amended legislation, with subsequent work recommendations influenced the formation of large residential properties in rural areas.

Why people move is an important issue for both researchers in the field and politicians, as the regional policy should be adapted to where people want to live and why they choose to move there. Previous studies have mainly focused on economic motives, but the living environment and nature’s impact has been increasingly highlighted in recent years. The importance of the property’s physical design for the decision to move, however, is less investigated. We have therefore examined whether and how those properties affected settlement in rural areas within the selected municipalities. The study consisted partly of a postal questionnaire to the property owners who hold these large residential properties with forest parcels included and semi-structured interviews with surveyors who carried out these missions.

Overall, we saw that large residential properties with forest and land was a reason for the counter-urbanization that has taken place because many of the migratory reasons given have been difficult to achieve with a different type of property. Although surveyors’ assessment differed in terms of details the main purpose to create appropriate and attractive residential properties without the productive forest damaged was fulfilled. We made the conclusion that the property formed, perceived as attractive by those who moved to these properties because they took advantage of the opportunities available with this accommodation.

The main focus of this paper is to describe the active hydraulic and sedimentary processes in downstream river reaches during flushing of sediments from reservoirs. During flushing extreme amounts of sediment may be released. Therefore, these processes are different than those downstream from dams and reservoirs not subjected to flushing. Hence, also the effects differ, which knowledge of may be of value for biologists, etc. During flushing of a reservoir a wave will be released to the downstream reaches. This wave can be divided into one water part and one sediment part. Initially they are in phase with each other, but with increased distance downstream from the dam, the transported sediment lags behind the water due to different traveling velocities. The paper treats when and where sedimentation occurs, and how this is related to the different traveling velocities of water and sediment. Also included are discussions on how the downstream effects during flushing differ from non-flushing effects, how visualization of effects can enhance both the analysis and communication with planners, politicians, etc., as well as discussions on how the studies of these effects can benefit from improved field-work methods.

Geoinformatics 2004, the 12th International Conference on Geoinformatics, is the premier research forum for Geospatial Information Research. It commenced in 1992 in Buffalo, and has been held every year since. Meetings have been held in North America and Asia in Beijing (1993), Calgary (1994), Hong Kong (1995), West Palm Beach (1996), Taipei (1997), Beijing (1998), Ann Arbor (1999), Monterey (2000), Bangkok (2001), Nanjing (2002), and Toronto (2003, cancelled due to the outbreak of SARS). This is the premier event organized by the University of Gävle, together with the Association of Chinese Professionals in Geographic Information Science (CPGIS-abroad).

This conference is the first of the series that takes place in Europe, hence the subtitle of the conference - bridging the Pacific and Atlantic. I believe it offers an opportunity for all professionals involved in research and development of geographic information systems, global position systems and remote sensing to discuss new theories and technologies around geoinformatics research.

Based on the extended abstracts and following advice from the program committee, the organizing committee selected 108 papers (involving 264 authors from 29 different countries) around 10 different themes included in the proceedings. The conference themes include some emerging research issues such as location-based services and geovisualization as well as long studied conventional issues. As a post-conference publication effort, some selected papers around special themes will go another round of review process to be published in special issues with some scientific journals.

The organization of the event is rather team-oriented work. On behalf of the organizing committee, I would like to thank CPGIS, the University of Gävle, our sponsors and all those individuals involved in making it a successful event, in particular, Kickan Fahlstedt, the conference secretary who took most administrative and organizational matters into her hands; Anders Brandt who read the papers and provided useful comments to the authors; Bengt Eriksson, Stig-Göran Mårtensson, and Bengt Rystedt who are always very supportive for the event; Peter Fisher and David Maguire who share their vision on current geoinformatics research; and all the authors who contribute with their papers of high quality.

Last but not least, the following colleagues or students deserve special thanks for their contributions to the organization of the conference: Gunter Göckelmann, Pia Ollert- Hallqvist, Anna Hansson, Neta Hedberg, Elisabeth Hugg, Mikael Johansson, Rebecca Jonsson, Hendrik Loch, Bengt-Olof Lundinger, Staffan Nygren, Kaj Wejander, and Wenjun Xie.

A case study of the Eskilstuna River in Sweden is presented. This study is carried out within the project KRIS-GIS®, a Swedish initiative of handling crisis situations, including flooding. The purpose is to show how different resolutions in input elevation data affect the resulting inundation maps. Terrain elevation points at the sides of the river were gathered from an airborne laser altimetry survey, and river bed elevations were gathered from an echosounding survey. The terrain model was constructed in ArcView GIS as a triangulated irregular network (TIN), which served as the base for all later modeling. The hydraulic modeling was done as one-dimensional steady flow in HEC-RAS flow routing software. High-resolution elevation data resulted in better inundation delineation than did lowresolution elevation data. If the mean water discharge was used in the modeling and if the river is narrow, a low resolution could even lead to that the river itself would not be marked as inundated. At high water discharges, the river was usually inundated, but there was great uncertainty if the riparian areas really would be flooded or not. With steep side slopes, the delineation of inundation becomes more certain, while at gentler side slopes, the flow is distributed on a larger surface with a risk that the raster cells will be incorrectly marked regarding inundation. Finally, the use of high-resolution elevation data compared with lowresolution data, makes estimates of friction factor, Manning’s n, relatively more important for correct results in inundation studies.

With the implementation of the Bologna declaration, European and other universities must change or adjust courses and programmes so they fit into the Bologna model. In Sweden this will take place during 2007. The intention with the declaration, for example, is that a basic course in one subject at one university should be treated as equivalent to the same type of course at another university. Once a year, the recently formed section for education of the Swedish Cartographic Society gathers university lecturers and others for an education conference to discuss matters concerning higher education in geomatics, geoinformatics, geography, etc. Last year’s conference identified the need for a harmonized course curriculum in basic GIS. One of the advantages of such a course is easier transfer of study records for inclusion of course credits in study programmes at other universities. Therefore, an attempt has been made to write a harmonized course curriculum for basic GIS. The course will contain about 50% common content and about 50% of content decided by the individual university. The common content will be described as learning outcomes, and then it is up to the universities to place the learning outcomes into a context. Thanks to this common core, the course can be given for such diverse programmes as archaeology, land surveying, or economy, and still be able to include the required knowledge for students to continue on more advanced courses at other universities.

The fields of hydrology and fluvial geomorphology get more and more attention in the general public. The reason for this is changed climate patterns with increased frequencies of storms and river flooding and as a result changed geomorphology and living conditions for the inhabitants of the area. With the development of 3D geovisualization, hydrological and geomorphological processes can be better simulated and visualized. Thus not only the domain specialists, but also the general public can appreciate very complex hydrological processes and resulting geomorphology. This is of great value since a high frequency of storms and flooding has been a big issue for politicians, planners, and the general public. It is in this sense that 3D geovisualization can be an important tool for analysis and communication. Complex hydrological and geomorphological processes can be effectively simulated and analyzed by the domain specialists while efficient and effective visualization provides a common platform for communication among domain specialists and the general public. This paper will discuss and illustrate these issues using a case study of geomorphology along the Reventazón River, downstream from the Cachí Reservoir in Costa Rica, due to the release of extreme amounts of sediment during flushing of the reservoir.

With the implementation of the Bologna declaration, many study programmes and course curricula needs to be updated and revised. This paper describes the current situation in Sweden regarding GIT educations and courses and whether a harmonization is needed. A survey was made to see which GIT courses that are given and at which level they are given at the various universities. For some universities, interviews were conducted about their courses’ contents and their strategies for determining course levels. Discussions were also made about harmonization of courses between Swedish universities. Some problems due to lack of harmonization was noted, which probably will be more severe in the future due to increased student mobility. To harmonize courses, Bloom’s revised taxonomy is put forward as a tool which is used to clearly state the level of the course in relation to learning objectives.

Determining bumpiness and inclination of surfaces is very important in many different areas, such as airports and at constructions sites. In this study, a surveying trolley and a remote controlled (RC) car were used to determine the bumpiness of two different surfaces. The aim with this study was to test the accuracy of a surveying trolley and an RC car to see how the accuracy can be increased with different observation methods. Total station, GPS and laser scanner surveying equipments were used, and all observations obtained by them were analysed. The laser scanner data was found to have the best precision. For that reason, it was accepted as the “true” data and it was used for comparing and evaluating other methods. It was found that the trolley and the RC car provided good height information with total stations and they were corresponding to the laser scanner data. When they were used with GPS, the accuracy was much lower. It was concluded that using two total stations is not increasing the accuracy, the RC car and the trolley are good measuring methods but not capable to inspect 1,2 mm tolerance for the floors, and finally, 2-3 cm positioning accuracy is obtainable when using GPS.

Several cities have implemented various projects to improve traffic safety in city centers.During 1970s and 1980s the city centers changed as the suburbs grew and large shopping centers were located outside the center. At the same time, several projects were initiated with construction of pedestrian streets and restriction of traffic in the center. In year 1994,shared-used areas were introduced in Sweden and these areas are often used in center environments.

In Sweden, municipalities are responsible for integrating security in public places and in comprehensive plans and detailed development plans. The National Board of Housing,Building and Planning is the authority for administrating planning issues and develop general guidance about planning. Traffic is one of their key issues, although today there are no concrete guidelines from the National Board of Housing, Building and Planningfor the design of traffic safety in city centers.

Traffic safety in city centers affects many people because the city center is a public place.It is therefore important that there are current guidelines available that are helpful for changes and improvements in traffic safety in the city center.

The purpose of this report is to formulate guidelines for planning city centers from a traffic safety perspective. The aim is that the guidelines can be applied in the design of smaller city centers for improving traffic safety. For this report two case studies were implemented that included inventories and observations of Bollnäs and Sandviken city centers. The results showed that many of the streets did not function well and that there was a lack of design in the city centre center from a traffic safety perspective, for example pedestrian crossings and car parks.

Inventories and observations are good methods to see how the traffic environment in the city center varies in use and function. The observations and inventories resulted in guidelines with recommendations for the design of streets and traffic in small city centers.

The objective of this study is to develop a multiple linear regression model that measures the relationship between the church services supply and the attendance to the services in the Uppsala diocese, Church of Sweden. By reviewing previous models and examining the nature of data available, two research questions were introduced, namely, the problem of omitted variables and the problem of spatial autocorrelation. For the first question, two methods were compared, namely, the Y-lag method and the first-differenced equation. Statistical tests then showed that the latter was more preferable for this study. For the second question, geographically weighted regression was used to examine the spatial variations in relationships estimated by above modeling strategies. However, no significant spatial variation was found for them. In conclusion, by using the ordinary least square estimation for the first-differenced equation the most suitable regression model was obtained. The data showed no need to consider the issue of spatial non-stationarity.

30. The application of multispectral analysis to reduce cloud interference

Huang, Yujie

University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för samhällsbyggnad. University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.

For multispectral Remote Sensing (RS) image analysis, a big problem is that original dataalways include Clouds-Interference (CI). Especially in the bad weather conditions, the CI is evidentin RS image. So during the pre-processing of RS image, the CI should be reduced as much aspossible. In this paper, reducing CI is researched as the central problem, so that much Ground-Objects Feature (GOF) can be obtained. An analysis about the clouds reflection in differentSpectral-Bands (SBs) was done based on optical theory and early researches. Moreover, therelationships between clouds reflection and ground-objects reflection are presented to understandwhat the Digital Number (DN) represented in each SB, and to reduce the impact of CI the Same DNSpectral Matching Method (SDN-SMM) based on the multispectral application is applied. Finally,two cases are tested using Matlab Programme to indicate the rationality and practicability of SDNSMM.About SDN-SMM, some advantages and disadvantages are concluded through discussion onfinal results. The method can be used in any kind of multispectral sensors image with simplecalculation, while, the original data of clouds-free region will not be changed. However, the qualityof CI reduction depends on the precision of clouds identification and the SB which is used forspectral position relationship creating. In the end of this paper, the improvement is also presentedfor the future work.

In this study, Artificial Neural Network (ANN) is used to check the integrity of the Global Positioning Recommended Minimum (GPRMC) sentences. The GPRMC sentences are the most common sentences transmitted by the Global Positioning System (GPS) devices. This sentence contains nearly every thing a GPS application needs. The data integrity is compared on the basis of the classification accuracy and the minimum error obtained using the ANN. The ANN requires data to be presented in a certain format supported by the learning process of the network. Therefore a certain amount of data processing is needed before training patterns are presented to the network. The data pre processing is done by the design and development of different algorithms in C# using Visual Studio.Net 2003. This study uses the BackPropagation (BP) feed forward multilayer ANN algorithm with the learning rate and the momentum as its parameters. The results are analyzed based on different ANN architectures, classification accuracy, Sum of Square Error (SSE), variables sensitivity analysis and training graph. The best obtained ANN architecture shows a good performance with the selection classification of 96.79 % and the selection sum of square error 0.2022. This study uses the ANN tool Trajan 6.0 Demonstrator.

A topographic surface can be modeled as a graph, a visibility graph in terms of how each point location is visible to every other. This paper demonstrates various structural properties of visibility patterns with a topographic surface from a graph perspective, which could be important for landscape planning. This paper illustrates the fact that the visibility graph with a topographic surface is a small-world. This finding implies that the average visual separation between any two point locations with a surface is very short (i.e. a small separation), and the visible locations to a given location have a high possibility of being visible to each other (i.e. a high clustering level). Additionally we show that the visibility graph exhibits an exponential distribution rather than a power law distribution, i.e. it is not scale-free, in contrast to many other real world networks.

A city can be topologically represented as a connectivity graph, consisting of nodes representing individual spaces and links if the corresponding spaces are intersected. It turns out in the space syntax literature that some defined topological metrics can capture human movement rates in individual spaces. In other words, the topological metrics are significantly correlated to human movement rates, and individual spaces can be ranked by the metrics for predicting human movement. However, this correlation has never been well justified. In this paper, we study the same issue by applying the weighted PageRank algorithm to the connectivity graph or space-space topology for ranking the individual spaces, and find surprisingly that: (1) the PageRank scores are better correlated to human movement rates than the space syntax metrics, and (2) the underlying space-space topology demonstrates small world and scale free properties. The findings provide a novel justification as to why space syntax, or topological analysis in general, can be used to predict human movement. We further conjecture that this kind of analysis is no more than predicting a drunkard's walking on a small world and scale free network.

Urban streets are hierarchically organized in the sense that a majority of streets are trivial, while a minority of streets is vital. This hierarchy can be simply, but elegantly, characterized by the 80/20 principle, i.e. 80% of streets are less connected (below the average), while 20% of streets are well connected (above the average); out of the 20%, there is 1% of streets that are extremely well connected. This paper, using a European city as an example, examined, at a much more detailed level, such street hierarchies from the perspective of geometric and topological properties. Based on an empirical study, we further proved a previous conjecture that a minority of streets accounts for a majority of traffic flow; more accurately, the 20% of top streets accommodate 80% of traffic flow (20/80), and the 1% of top streets account for more than 20% of traffic flow (1/20). Our study provides new evidence as to how a city is (self-)organized, contributing to the understanding of cities and their evolution using increasingly available mobility geographic information.

A qualitative location (QL) refers to the reference of a spatial location using linguistic terms such as qualitative descriptions and qualitative spatial relations with other geo-referenced features. Qualitative locations will be increasingly more popular in the future, driven by theoretical, technological, and database developments. Multiplicity and uncertainty are two innate characteristics of QLs. In other words, a QL often has multiple target locations (multiplicity), and the target locations sometimes cannot be pinpointed exactly due to the qualitative nature (uncertainty) of the qualitative descriptions and relations. The presence of the characteristics imposes research challenges on visualization of QL in geographic information systems (GIS). In response to the visualization challenges we discuss four strategies—namely proportional symbol mapping, fog map, fuzzy 3D surface, and fuzzy-logic-based animation—for the visualization of QL referents in GIS. These strategies combine conventional mapping and advanced interactive visualization methods. Each of them is suitable for one or more scenarios, depending on the presence of either one or both of the two characteristics. All illustrations and related animations are also available at http://www.ggy.uga.edu/people/faculty/xyao/VisQL.html.

This paper proposes a novel generalization model for selecting characteristic streets in an urban street network. This model retains the central structure of a street network. It relies on a structural representation of a street network using graph principles where vertices represent named streets and links represent street intersections. Based on this representation, so-called connectivity graph, centrality measures are introduced to qualify the status of each individual vertex within the graph. We show that these measures can be used for characterizing the structural properties of an urban street network, and for the selection of important streets. The proposed approach is validated by a case study applied to a middle-sized Swedish city.

The research field of transportation demand forecasting has started to focus on disaggregate travel behavior and micro-simulation models. To create data infrastructure, disaggregate trip surveys are conducted and large numbers of observations are collected. To efficiently exploit these surveys, the transfer of the individual trip data to a GIS must start with the development of a solid conceptual data model that fully captures the semantic richness of the application domain and emphasizes its spatio-temporal properties. This paper presents a data modeling process that is based on a combination of complex system theory and the object-oriented paradigm and produced an object-oriented spatio-temporal data model. Main domain entities are modeled as highly structured classes. They encapsulate a memory of their time bound connections and states. Observation data sets are sampled from the origin-destination survey conducted in the Québec region in 1991. This survey incorporated street networks and activity places. The model was smoothly implemented into a proof-of-concept database prototype hosted by an object-oriented GIS shell. The prototype offers a means to navigate through a nested hierarchy of objects, providing a description of an individual’s travel behavior over space and time. The objects have a solid conceptual basis and can meet the needs of scientific research such as hypothesis formulation, simulation, forecasting and induction.

The authors propose a topological analysis of large urban street networks based on acomputational and functional graph representation. This representation gives a functional view inwhich vertices represent named streets and edges represent street intersections. A range of graphmeasures, including street connectivity, average path length, and clustering coefficient, are computedfor structural analysis. In order to characterise different clustering degrees of streets in a streetnetwork they generalise the clustering coefficient to a k-clustering coefficient that takes into accountk neighbours. Based on validations applied to three cities, the authors show that large urban streetnetworks form small-world networks but exhibit no scale-free property.

48. Selection of streets from a network using self-organizing maps

Jiang, Bin

et al.

University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för samhällsbyggnad.

We propose a novel approach to selection of important streets from a network, based on the technique of a self-organizing map (SOM), an artificial neural network algorithm for data clustering and visualization. Using the SOM training process, the approach derives a set of neurons by considering multiple attributes including topological, geometric and semantic properties of streets. The set of neurons constitutes a SOM, with which each neuron corresponds to a set of streets with similar properties. Our approach creates an exploratory linkage between the SOM and a street network, thus providing a visual tool to cluster streets interactively. The approach is validated with a case study applied to the street network in Munich, Germany.